Fluid supported apparatus



1966 A. L. WITCHEY 3, ,0

FLUID SUPPORTED APPARATUS Filed May 17, 1962 5 Sheets-Sheet 1 INV ENTOR. 415.577 Z. W/rmzr Arraxwzr A. L. WITCHEY FLUID SUPPORTED APPARATUSNov. 1, 1966 5 Sheets-Sheet 2 Filed May 17, 1962 INV EN TOR. Azazn- Z. lV/rawir BY Arr-mews) United States Patent FLUID SUPPORTED APPARATUSAlbert L. Witchey, Erlton, N .J., assignor to Radio Corporation ofAmerica, a corporation of Delaware Filed May 17, 1962, Ser. No. 195,4649 Claims. (Cl. 179100.2)

This invention relates to fluid supported apparatus, and particularly tofluid driven and fluid supported apparatus, such as devices includingturbines and fluid bearings.

The invention is especially suitable for use in recording apparatus,such as a magnetic drum recording device, and involves mechanism forenabling a recording surface to be rotated at very high speeds. When theterms recording apparatus or recording surface are used herein, itshould be understeod that reproducing, as well as recording, may beaccomplished by such apparatus or on such surface.

Turbines have been proposed wherein a shaft is driven by means of streamof air. It has also been proposed to support a turbine driven shaft byair bearings. The pneumatic power requirements (the volume ofpressurized air used per minute) of known air bearing supported turbinesmay be excessive, especially when high speeds of the order of 10,000r.p.m. are desired. Moreover, designs for air bearing supported turbinesystems have, as a rule, been complex in that they involve amultiplicity of ducts and orifices which are in precise alignment witheach other.

It is an object of the present invention to provide improved fluidsupported and driven apparatus wherein the foregoing disadvantages ofknown air bearing supported turbines are substantially eliminated.

It is a still further object of the present invention to provideimproved fluid supported and driven apparatus which is highly eflicientin operation, particularly insofar as the pneumatic power required isconcerned.

It is a still further object of the present invention to provide animproved pneumatic turbine which is supported on penumatic bearings andwhich has a pneumatic power consumption of the same order of magnitudeas the electric power, consumption of an electric motor which would berequired in lieu of the turbine to provide equivalent results.

It is a still further object of the present invention to provideimproved recording apparatus and particularly an improved magnetic drumdevice.

It is a still further object of the present invention to providemagnetic recording apparatus capable of direct magnetic recording ofhigh frequency signals of the order of 50 megacycles per second.

Briefly, fluid supported and driven apparatus embodying the invention isarranged so that the same set of pressurized fluid supply jets whichsupplies turbine power also establishes a fluid bearing for supportingthe turbine.

Apparatus embodying the invention may, for example, comprise a statorand a rotor having opposed, complementary, arcuate surfaces. The statorand rotor may respectively have pressurized fluid supply jets andbuckets in their opposed, complementary, arcuate surfaces. Pressurizedair emanating from the stator jets both drives the rotor and establishesan air bearing between the opposed, arcuate rotor and stator surfacesfor supporting the rotor.

The invention itself, both as to its organization and method ofoperation, as well as additional objects and advantages thereof, willbecome more readily apparent from a reading of the following descriptionin connection with the accompanying drawings, in which:

FIG. 1 is a perspective view, partially broken away, showing a magneticdrum device embodying the invention;

FIG. 2 is a vertical sectional view taken along the line 22 in FIG. 1,and viewed in the direction of the apice pended arrows showing in detailthe magnetic drum device;

FIG. 3 is a sectional view taken along the line 33 in FIG. 2 and viewedin the direction of the appended arrows;

FIG. 4 is a sectional view taken along the line 44 in FIG. 2 and viewedin the direction of the appended arrows; and

FIG. 5 is a fragmentary, perspective view showing a portion of the rotorof the magnetic drum device shown in the foregoing figures.

Referring more particularly to FIG. 1, there is shown a magnetic drumrecording device which is an illustrative embodiment of fluid supportedand fluid driven apparatus according to the invention. The fluid 'whichis used in the device illustrated in FIG. 1 is air. Other fluids, suchas gases other than air, or liquids, preferably of low 'viscosity, maybe used alternatively. However, use of air is preferred because it isreadily available and may be pressurized with compressors of the typewhich are generally available.

The magnetic drum device includes a rotor 10 in the form of a ringhaving a cylindrical outer peripheral surface coated with magnetizablematerial 12, which may be a magnetic oxide. This ring provides amagnetic drum record. The rotor 10 is located around a stator likeassembly 14, referred to for convenience as a stator. This stator ismounted in a journal on a panel 16. The stator may be free to rotate onits axis, or it may be rotated on its axis by an electric motor 18 whichis secured to the panel. A pulley 20 on the shaft of the motor 18 isbelt coupled to another pulley which is connected to the stator.Alternatively, the stator 14 may be held stationary.

A magnetic head 22 is supported by an L-shaped bracket 24. Feet 26 ofthe bracket 24 are attached to the stator 14 so that the head 22 mayeither be stationary or rotate with the stator, as desired. The head 22may desirably be a multi-channel head having a plurality of side-by-sidehead units which scan adjacent record tracks on the magnetizable coating12 on the rotor 10. A slip ring assembly (not shown) may be mounted onthe stator 14 coaxially therewith. The output leads from the head 22 maybe connected to the slip rings of the-assembly. A brush assembly (notshown) mounted on the panel 16, for example, by means of a bracket maycooperate with the slip ring assembly for deriving output signals fromthe head 22 when the head rotates with the stator 14.

The internal periphery of the rotor 10 is arcuate in shape. Moreparticularly the inner periphery of the rotor 10 is inwardly convex, asviewed in a cross-section taken in an axial plane (see FIG. 2) the rotorbeing generally toroidal in shape. This inwardly convex, arcuate surfaceis opposed to a complementary, outwardly concave, arcuate surface (whenviewed in like-section) in the stator. The rotor 10 and stator 14 aredisposed in nested relationship. In other words, the rotor is seated inthe stator. A small clearance of the order of 0.001 inch may be providedbetween the opposed rotor and stator surfaces.

An array of air propulsion jets (shown at 108 in FIGS. 2 and 3) extendsinwardly into the stator from its internally concave, arcuate surface.The inwardly convex surface of the rotor has an array of bucket scoopnotches 34 therein (see FIG. 5). Thus, when compressed air is exhaustedinto the space between the opposed arcuate surfaces of the rotor 10 andstator 14, the rotor is propelled in one direction by the streams of airimpinging on the bucket scoops. The stator tends to rotate in theopposite direction from the rotor because of jet reaction forces. Theair from the jets also flows between the opposed surfaces of the statorand rotor and fills the clearance therebetween. The rotor thereforefloats on a film of air (a hydrostatic air bearing), as it is propelledby the air from the propulsion jets in the stator. Extremely highspeedsof rotation are possible with this magnetic drumdevice. These speeds mayexceed 10,000 rpm. when the device is operated in air. Even higherspeedsare possible when the device is operated in a vacuum chamber.

The etficiency of the device is extremely high, since the frictionalforces are substantially eliminated due to the air bearing provided bythe film of 'air established between the rotor and stator. The drag dueto viscous shear losses is also reduced, especially when the stator androtor rotate, since the relative velocity of the air and the movingstator and rotor surfaces is small. Pneumatic power required in terms ofthe volume of air and pressure of air required (the dimensions ofpneumatic power may be cubic feet, pounds per square inch-seconds) isalso reduced because the bucket scoops are arranged opposite to thepropulsion jets to utilize the maximum thrust of the air as it emanatesfrom the jets. Since the jets and scoops are directly opposite eachother, the velocity of the air is not appreciably diminished before theair impinges upon the scoops. The pneumatic power requirements of thedevice are also low because the complementary, opposed, arcuate surfaceof the rotor and stator confine and direct the air as it leaves thepropulsion jets. The air therefore cannot disperse appreciably as, forexample, would ''be the case if flat or cylindrical stator and rotorsurfaces were opposed to each other.

It has been found that a magnetic drum device of the type describedherein, when operated at speeds of the order 'of 10,000 rpm. consumes nomore pneumatic power than the equivalent amount of electric power whichwould be consumed by an electric motor for driving such a drum.

The details of construction of a magnetic drum device such as shown inFIG. 1 are illustrated in FIGS. 2 to -5. The rotor 10 is a ring made,for example, of aluminum. The outer periphery 28 of the rotor iscylindrical. The inner periphery 30 of the rotor 10 is as arcuate inshape and semicircular in cross section as viewed in FIG. 2. The sidewalls 32 of the rotor which extend between the outer periphery 28 andthe inner periphery 30 thereof are in parallel planes. The cylindricalbucket scoop notches 34 are milled into the inner periphery 30 of therotor. The notches 34 lie approximately in a plane perpendicular to theaxis of the rotor which plane bisects the rotor (see FIG.

The stator 14 is a two part assembly. The parts of the stator areessentially an outer cylinder 36 and an inner cylinder 38 joined alongmating surfaces 37 and 39. The outeredges of the mating surfaces 37 and39 of the stator parts 36 and 38, respectively have circular, quadrantalcut away portions 41 and 43 milled therein. These portions '41- and 43form the inwardly concave surface of semicircular cross section in anaxial plane (see FIG. 2) in the outer periphery of the stator 14' whenthe stator parts 36 and 38 are joined in mating relationship with eachother. 'This peripheral inwardly concave, arcuate surface 41, 43,provides the seat for the inwardly couvex, inner periphery 30 of therotor 10. The transverse diameter of this peripheral surface 41, 43 isslightly larger "than the transverse diameter of the convex, innerperipheral surface of the rotor 10. Accordingly, a slight clearance45(e.g., 0.001 inch) is provided between the stator and the rotor 14.The propulsion jets and duct work for directing air to the propulsionjets are formed at the mating surfaces 37 and 39 of the stator parts 36and 38, and are described hereinafter. The parts 36 and 38 are heldtogether by a multiplicity of screws 40 which extend through tapped,aligned holes in both parts 36 and 38.

The outer stator part 36 has a central hole 42 which surrounds a centralhub 44 of the inner stator part 38. This hub has a central hole 46 intowhich the end of a flanged shaft 48 extends. A flange 50 on the shaft 48has a multiplicity of tapped holes therein which are in alignment withtapped holes in the hub 44. Screws 52 in these aligned, tapped holesjoin the shaft 48 to the stator assembly 14.

The shaft 48 extends through the panel16 and is journaled in ballbearings 54 and 56. The outer races of these ball bearings are mountedin a flanged collar 58.

This collar 58 extends through the panel 16. A flange 60 on the end ofthe collar has a plurality of tapped holes therein which are alignedwith tapped holes in the panel 16. Screws 62 in these tapped, alignedholes fasten the flange 60 to the panel 16.

A pulley 64 is attached to the shaft 48 by means of a set screw 66. Abelt 68 (shown in phantom) may be trained around the pulley 64, when itis desired to drive the stator by meansof a motor, as shown in FIG. 1.

A cylindrical shell 70, attached at one end to the panel 16 by means ofscrews 72,? surrounds the collar 58 and the pulley 68. r The free end ofthe shell 70 is closed by an apertured disc 74 which is attache-d to thefree'end of the shell 70 by means of screws 76. A set screw 88 which isscrewed into a tapped hole in the shell70 can be adjusted to engage acooperating notch 92 in the pulley 64 for holding the shaft 48 and thestator stationary.

A flanged, cylindrical bearing member 78, which may be made of bronzeOilite bearing material, closes the aperture in the disc 74. The bearingmember 78 is also apertured and has a conical, tapped hole 80 into whicha compressed air fitting 82 is seated. This fittin-g82 is adapted toreceive the end of a hose from an air compressor.

The shaft 48 is formed with a blind, axial bore 84. i The openend ofthis bore is counterbored and receives the cylindrical periphery 86 ofthe Oilite bearing member 78. The periphery 86 therefore providesanother bearing for supporting the shaft 48.

The formation and construction of the duct work which provides thepropulsion jets are best shown in FIGS. 3 and 4. Two passages 94 and 96are drilled through the hub 44 of the inner cylindrical part 38 of thestator and through the shaft 48 into the blind, axial bore 84, each at asuitable angle to the axis of the shaft48 in substantially a commonplane and disposed in mirror image relation with respect to the axis.Circular notches 98 and 100 are cut in the outer stator part 36 and inthe inner stator part 38, respectively. These notches jointly form acircular groove 102 which communicates with the open, outer ends of theholes 94 and 96. A plurality of radial grooves 104 are cut in thesurface 39 of'the stator part 38 which mates with the surface 37 of theother stator part 36. These radial grooves 104 communicate the circulargroove 102 with another, gnarrow,

circular groove 106 cut into the surface 39 of the stator part 38. Alarge number of grooves, 108 are cut in the surface 39 of the statorpart '38 at similar angles to radial lines from the axis. These groovesform the propulsion jets. It should, be noted that the grooves 108 areso disposed that each. of them communicates with the pe- 'ripheralgroove which forms the seat in the stator 14 of the rotor 10 at thecenter of that seat. Accordingly, the propulsion jets are directlyopposite to, and in alignment with, the, semicircular notches 34 whichprovide the bucket scoops on the inner periphery 30 of the rotor 10. Thepropulsion jet grooves 108 are all cut at the same angle (for example,31.3) with respect to lines tangent to the outer periphery of the statorpart 38 at the entrances of these grooves into the stator part 38. Theangle is selected to achieve the maximum tangential component of airthrust upon the scoop notches 34 without greatly enlarging the orificesformed by the propulsion jet grooves 108 in the peripheral, concavestator groove.

In operation, pressurized air flows through the fitting 82 into theblind bore 84 in the shaft 48. The pressure of this air, when a rotorhaving an outer diameter of approximately 8 inches, for example, is tobe driven at about 10,000 rpm. may be 60 p.s.i.

The air flows through the passages 94 and 96 into the circular grove102. The velocity of the air increases as it flows into the radialgrooves 104 which are of smaller transverse diameter than the circulargroove 102 and therefore the radial grooves 104 act as nozzles. Thevelocity of the air further increases as the air flows through thepropulsion jet grooves 108. The air emanates from these grooves 108 atextremely high velocity. For example, in the case of the air pressureand rotor size referred to above, the velocity of the air escaping fromeach of the propulsion jets may be 1000 feet per second. This extremelyhigh velocity air impinges upon the semicircular notches 34. Thesenotches catch the air and convert the force of the air into rotarymotion of the rotor 10. After impinging upon the scoop notches 34, theair is directed into the clearance 45 between the rotor and the statorbecause of the arcuate shape of this clearance and because thepropulsion jets emanate in the center of the clearance 45.

The escaping, pressurized air establishes a hydrostatic air bearing inthe clearance 45. This bearing provides both axial and radial supportfor the rotor 10. In other words, the escaping air provides a film ofair in the clearance 45 between the rotor and stator 14 as this airdrives the rotor 10. Extremely high speeds of rotation of the rotor arepossible since (1) there is substantially no friction between the statorand the rotor because of the air bearing therebetween, and (2) theviscous drag between the rotor and the stator is small because therelative velocity between the moving air and the rotating rotor is verylow. The pneumatic power required by the device is small and theover-all efficiency of the device is high and comparable to theefiiciency of magnetic drums which are driven by electric motors.

Three modes of operation of the device are possible as follows:

(1) The set screw 88 is connected to the pulley 64 and holds the stator14 stationary so that the rotor 10 alone rotates.

(2) The set screw 88 is withdrawn and the stator 14 is allowed to rotateunder the influence of reaction forces developed by the escaping airfrom the propulsion jets.

(3) The belt 68 is coupled to a motor 18 (as shown in FIG. 1) and thestator 14 is directly driven while the rotor is air driven in the samedirection as the stator 14.

In the second mode of operation noted above, the relative speed of thestator with respect to the rotor is greater than when the stator is heldstationary with the set screw 88. The relative stator to rotor speedmay, for example, be 14,000 r.p.m. when the stator is allowed to rotate.

The efficiency of operation also increases, since losses due to viscousshear effects are reduced. It is believed that, when the apparatus isoperating in a gaseous environment of finite pressure (air underatmospheric pressure), viscous shear losses depend directly upon theabsolute speed of the rotor 10 through the atmosphere. The absolutespeed of the rotor, when the stator 14 is allowed to rotate under theinfluence of reaction forces developed by air escaping from thepropulsion jet grooves 108 (FIG., 3), is less than when the stator 14 isheld stationary. Thus, the viscous shear losses are reduced while therelative rotor to stator speed is increased in the second mode ofoperation.

When the motor 18 (FIG. 1) drives the stator 14 in the same direction asthe rotor 10, as in mode (3) noted above, the absolute rotor speed isgreater than when the rotor is held stationary because the kineticenergy of stator rotation is added to the energy of the air escapingfrom the propulsion jet grooves 108 (FIG. 3). Efficiency of operation issomewhat less than in mode 1), since viscous shear losses rise withabsolute rotor speed. If the pressure of the atmosphere surrounding theapparatus is reduced, as, for example, when the apparatus is operated ina vacuum, the efficiency would remain high and rotor speed would befurther increased. In the absence 6 of appreciable viscous shear andother viscous drag effects, the speed of rotation of the rotor islimited, as a practical matter, only by the capacity of the compressedair supply and the strength of the materials from which the rotor isconstructed.

When the device is used for magnetic recording, extremely highfrequencies may 'be recorded on the magnetizable coating 12, since therelative head to record speed is very high. As is well known in themagnetic recording art, the recorded signal wavelengths depend upon thehead-to-record speed as well as the frequency of the signals applied tohead. Since the record rotates at very high speed, the recordedwavelengths may be much larger than the wavelengths of the signalsapplied to the head. Since the minimum length of the wavelengths whichcan be recorded on a magnetic record is limited by the characteristicsof that magnetic record, the above described magnetic recording devicemakes possible the recording of very high frequency signals (forexample, 50 megacycles per second with known ma-gnetizable materials).

From the foregoing description, it will be apparent that there has beenprovided improved fluid supported and fluid driven apparatus which isespecially suitable for use in magnetic recording devices and wherebyhigh frequency signals may be recorded. Uses of the invention other thanin magnetic recording, as well as variations in construction andoperation of apparatus described herein, all coming within the scope ofthe invention will undoubtedly present themselves to those skilled inthe art. Accordingly, the foregoing description should be taken merelyas illustrative and not in any limiting sense.

What is claimed is:

1. Fluid supported apparatus comprising (a) a rotor and a statorexhibiting complementary, opposed, arcuate surfaces having terminationpoints and disposed in nested relationship with each other,

(b) said stator having a plurality of propulsion jets therein emanatingfrom its said arcuate surface,

(c) said rotor having a plurality of bucket scoops therein extendinginto its said arcuate surface and disposed opposite to said jets, and

(d) means for applying pressurized fluid through said jets to impingeagainst said bucket scoops for propelling said rotor with said fluid,

said pressurized fluid being exhausted from between said rotor and saidstator arcuate surfaces at said termination points subsequent to theimpingement against said bucket scoops so as to establish a fluidbearing between said rotor and said stator.

2. A fluid supported turbine comprising (a) a first member,

(b) a second member about which said first member is rotatable, saidfirst and second members respectively having opposed surfaces ofrevolution, having termination points being disposed substantiallyopposite each other r (c) said first member surface having a pluralityof propulsion jets therein,

((1) said second member surface having a plurality of bucket scoopsdisposed in alignment with said jets, and

(e) means for applying pressurized fluid through said jets to impingeagainst said bucket scoops for propelling said first member with saidfluid,

said pressurized fluid exhausted from between the surfaces of revolutionof said first and second members at said termination points subsequentto the impingement against said bucket scoops so as to establish a fluidbearing between said first and second members,

3. Fluid supported apparatus comprising (a) a rotor and a stator havingcomplementary, op-

posed, arcuate surfaces,

(b) said stator having a plurality of propulsion jets therein emanatingfrom its said arcuate surface,

(c) said rotor having a plurality of bucket scoops therein extendinginto its said arcuate surface and disposed opposite to said jets,

(d) means for rotatably mounting said stator, and

(e) means for applying pressurized fluid through said jets and onto saidbucket scoops for developing action and reaction forces for rotatingsaid rotor and stator in opposite directions while simultaneouslyestablishing a hydrostatic fluid bearing between said surfaces.

4. A fluid supported turbine comprising (a) a rotor and a stator,

(b) means for rotata-bly mounting said stator,

(c) said rotor and said stator having complementary,

opposed, arcuate surfaces disposed in nested relationship to provide abearing clearance therebetween,

(d) said stator having a plurality of propulsion jets therein emanatingfrom its said arcuate surface,

(e) said rotor having a plurality of bucket scoops therein' extendinginto its said arcuate surface and disposed opposite to said jets,

(f) means for supplying pressurized fluid through said jets for floatingsaid rotor on a film of fluid formed in said bearing clearance andsimultaneously impinging said fluid on said bucket scoops to rotate saidrotor, and

(g) drive means for rotating said stator in the same direction ofrotation as said rotor.

5. Recording apparatus comprising (a) a rotor and a stat-or havingcomplementary, opposed, arcuate surfaces which define a toroidal passagebetween said opposed surfaces,

(b) said stator having a plurality of propulsion jets therein extendingfrom the center of its said arcuate surface,

(c) said rotor having a plurality of bucket scoops therein extendingfrom the center of its said arcuate surface and disposed opposite tosaid jets,

(d) a recording surface on one of said stator and rotor,

(e) a transducer mounted on the other of said stator and rotor anddisposed in scanning relationship with said recording surface, and

(f) means for supplying pressurized fluid through said jets and ontosaid scoops for simultaneously establishing a combined axial and radialfluid bearing between said opposed surfaces and propelling said rotorwith said fluid.

6. Recording apparatus comprising (a) a cylindrical ring rotor,

(b) a cylindrical stator,

(c) said rotor and stator having complementary, opposed, arcuatesurfaces disposed in nested relationship and defining a clearancetherebetween of arcuate cross-sectional shape,

(d) said stator having a plurality of propulsion jets therein extendingfrom the center of its said arcuate surface,

(e) said rotor having a plurality of bucket scoops therein extendingtherein from its said. arcuate surface and disposed opposite to saidjets,

(f) a recording surface on the surface of said rotor opposite to itssaid arcuate surface,

(g) a transducer mounted on said stator and disposed in scanningrelationship with said recording surface, and

(h) means for supplying pressurized fluid through said jets forsimultaneously establishing a fluid bearing in said clearance andpropelling said rotor by impingement-of said fluid against said scoops.

7. Apparatus for utilizing pressurized air comprising (a) a cylindricalring having an inner periphery semicircular in cross-section,

(b) a cylinder having a notch around the outer periphery thereof, saidnotch being semicircular 'in crosssection and having a radius largerthan said semicircular ring inner periphery,

(c) said ring being disposed around said cylinder with said ring innerperiphery nested in said notch, said inner and outer peripheries endingat termination points disposed substantially opposite each other (d)said cylinder having a plurality of spaced orifices therein extendingfrom the surface of said notch, said orifices respectively beingoriented at a predetermined acute angle With respect, to lines tangentto said cylinder at the entrance thereof into said cylinder, 7 (e) saidring having a plurality of notches therein spaced from each other alongsaid inner periphery thereof, and (f) means for applying pressurized airthrough said orifices to impinge against said ring notches for drivingsaid ring,

said pressurized air being exhausted from between said ring and saidcylinder. at said peripheral termination points subsequent to theimpingement against said ring notches so as to establish an air bearingbetween said ring and said cylinder. 8. Magnetic recording apparatus forcooperation with a magnetic head and. for utilizing pressurized aircomprising (a) a cylindrical ring having an inner periphery semicircularin cross-section,

(b) a cylinder having a notch around the outer periphery thereof, saidnotch being semicircular in crosssection and having a radius larger thansaid semicircular ring inner periphery,

(c) the outer, peripheral surface of said ring being cylindrical,

(d) a magnetizable coating on said ring outer peripheral surfacedefining a magnetic record,

(e) said ring being disposed around said cylinder with said ring innerperiphery nested in said notch, means for mounting said ring and saidcylinder adjacent said magnetic headso that said magnetizable coatingcooperates with said magnetic head,

(f) said cylinder having a plurality of spaced orifices extendingtherein from the surface of said notch, said orifices respectively beingoriented at a pre determined acute angle with respect to lines tangentto said cylinder at the entrance thereof into said cylinder,

(g) said ring having a plurality of scoop notches therein spaced fromeach other along said inner peripher thereof, and

(h) means for applying said pressurized air through said orifices andonto said scoop notches for simultaneously driving said ring andestablishing an air bearing for supporting said ring.

9. Apparatus for utilizing pressurized air comprising (a) a cylindricalring having an inner periphery semicircular in cross-section,

(b) a cylinder having a notch around the outer periphery thereof, saidnotch being semicircular in crosssection and having a radius. largerthan said semicircular ring inner periphery,

(c) said ring being disposed around said cylinder with said ring innerperiphery nested in said notch,

(d) said cylinder having a plurality of spaced orifices thereinextending from the surface of said notch, said orifices respectivelybeing oriented at predetermined acute angles with respect to linestangent to said cylinder at the entrace thereof into said cylinder,

(e) a shaft connected to said cylinder,

(f) bearing means rotatably supporting said shaft,

( g) said shaft having an axial bore therein,

(h) said cylinder having passages therethrough c0m-,

municating said orifices with said shaft bore,

References Cited by the Examiner UNITED STATES PATENTS 2,602,632 7/1952Serduke et a1.

Mathiesen.

Baumeister.

Riddler et a1. 179100 Quade 340174.1 Uritis 179-1002 Quade et a1340174.1 Levene 340174.1

10 BERNARD KONICK, Primary Examiner.

IRVING SRAGOW, Examiner. H. D. VOLK, G. LIEBERSTEIN, AssistantExaminers.

9. APPARATUS FOR UTILIZING PRESSURE AIR COMPRISING (A) A CYLINDRICALRING HAVING AN INNER PERIPHERY SEMICIRCULAR IN CROSS-SECTION, (B) ACYLINDER HAVING A NOTCH AROUND THE OUTER PERIPHERY THEREOF, SAID NOTCHBEING SEMICIRCULAR IN CROSSSECTION AND HAVING A RADIUS LARGER THAN SAIDSEMICIRCULAR RING INNER PERIPHERY, (C) SAID RING BEING DISPOSED AROUNDSAID CYLINDER WITH SAID RING INNER PERIPHERY NESTED IN SAID NOTCH, (D)SAID CYLINDER HAVING A PLURALITY OF SPACED ORIFICES THEREIN EXTENDINGFROM THE SURFACE OF SAID NOTCH, SAID ORIFICES RESPECTIVELY BEINGORIENTED AT PREDETERMINED ACUTE ANGLES WITH RESPECT TO LINES TANGENT TOSAID CYLINDER AT THE ENTRANCE THEREOF INTO SAID CYLINDER, (E) A SHAFTCONNECTED TO SAID CYLINDER, (F) BEARING MEANS ROTATABLY SUPPORTING SAIDSHAFT, (G) SAID SHAFT HAVING AN AXIAL BORE THEREIN, (H) SAID CYLINDERHAVING PASSAGES THERETHROUGH COMMUNICATING SAID ORIFICES WITH SAID SHAFTBORE, (I) SAID RING HAVING A PLURALITY OF SCOOP NOTCHES THEREIN SPACEDFROM EACH OTHER ALONG SAID INNER PERIPHERY THEREOF, AND (J) MEANS FORFLOWING SAID PRESSURIZED AIR THROUGH L SAID SHAFT BORE, SAID PASSAGESAND SAID ORIFICES AND ONTO SAID SCOOP NOTCHES FOR SIMULTANEOUSLY DRIVINGSAID RING AND ESTABLISHING AN AIR BEARING FOR SUPPORTIN SAID RING.